1. ABOUT SCRUM
Scrum is a framework within which people can address complex adaptive problems, while productively and creatively delivering products of the highest possible value.
Scrum is:
- Lightweight
- Simple to understand
- Difficult to master
Scrum is not a process or a technique for building products, rather, it is a framework within which you can employ various processes and techniques that fit your organization’s needs. Scrum makes clear the relative efficacy of your product management and development practices so that you can improve.
Scrum has been used for a variety of work, but has initially been most popular for delivering software based products. Because Scrum employs an empirical approach, a team would incrementally deliver work to mitigate risks and increase understanding.
Scrum provides a simple structure of roles, events, artifacts, and rules. Scrum teams are responsible for creating and adapting their processes within this framework. Scrum’s management practices are similar to those of eXtreme Programming (XP), but, unlike XP, Scrum does not prescribe specific engineering practices.
2. SCRUM ROLES
1. Product Owner
The Product Owner is a leadership role that is responsible for maximizing the value of the product and the work of the Development Team. How this is done may vary widely across organizations, Scrum Teams, and individuals.
The Product Owner is the sole person responsible for managing the Product Backlog. Product Backlog management includes:
- Clearly expressing Product Backlog items
- Ordering the items in the Product Backlog to best achieve goals and missions
- Ensuring the value of the work the Development Team performs
- Ensuring that the Product Backlog is visible, transparent, and clear to all, and shows what the Scrum Team will work on next
- Ensuring the Development Team understands items in the Product Backlog to the level needed. The Product Owner may do the above work, or have members of the Development Team do it. However, the Product Owner remains accountable for the value being delivered by the team
2. The development team
The Development Team consists of professionals who do the work of delivering a potentially releasable Increment of “Done” product at the end of each Sprint. Only members of the Development Team create the Increment.
Development Teams are structured and empowered by the organization to organize and manage their own work. The resulting synergy optimizes the Development Team’s overall efficiency and effectiveness.
Development Teams have the following characteristics:
- They are self-organizing. No one (not even the Scrum Master or Product Owner) tells the Development Team how to turn Product Backlog into Increments of potentially releasable functionality
- Development Teams are cross-functional, with all of the skills as a team necessary to create a product Increment
- Scrum recognizes no titles for Development Team members other than Developer, regardless of the work being performed by the person; there are no exceptions to this rule
- Individual Development Team members may have specialized skills and areas of focus, but accountability belongs to the Development Team as a whole
- Development Teams do not contain sub-teams dedicated to particular domains like testing or business analysis.
Optimal Development Team size is small enough to remain nimble and large enough to complete significant work. Smaller Development Teams may encounter skill constraints during the Sprint, causing the Development Team to be unable to deliver a potentially releasable Increment. Large Development Teams may generate too much complexity for an empirical process to manage.
3. Scrum Master
The Scrum Master is responsible for ensuring Scrum is understood and enacted. Scrum Masters do this by ensuring that the Scrum Team adheres to Scrum theory, practices, and rules. The Scrum Master is a servant-leader for the Scrum Team.
The Scrum Master serves both the Product Owner and the Development Team in several ways, including:
- Teaching the Scrum Team to understand the need for clear and concise Product Backlog items
- Facilitating Scrum events as requested or needed
- Coaching the Development Team in self-organization and cross-functionality
- Teaching and helping the Development Team to create high-value products
- Removing impediments to the Development Team’s progress
The Scrum Master helps those outside the Scrum Team understand which of their interactions with the Scrum Team are helpful and which aren’t. Scrum Master helps everyone change these interactions to maximize the value created by the Scrum Team.
3. SCRUM EVENTS
The heart of Scrum is a Sprint, a time-box of one month or less during which a “Done”, useable, and potentially releasable product Increment is created. Sprints best have consistent durations throughout a development effort. A new Sprint starts immediately after the conclusion of the previous Sprint.
Sprints contain and consist of the Sprint Planning, Daily Scrums, the development work, the Sprint Review, and the Sprint Retrospective.
Each Sprint may be considered a project with no more than a one-month horizon. Like projects, Sprints are used to accomplish something. Each Sprint has a definition of what is to be built, a design and flexible plan that will guide building it, the work, and the resultant product.
The Sprint Goal is an objective set for the Sprint that can be met through the implementation of Product Backlog items. It provides guidance to the Development Team on why it is building the Increment. It is created during the Sprint Planning meeting. The Sprint Goal gives the Development Team some flexibility regarding the functionality implemented within the Sprint. The selected Product Backlog items deliver one coherent function, which can be the Sprint Goal. As the Development Team works, it keeps the Sprint Goal in mind. In order to satisfy the Sprint Goal, it implements the functionality and technology.
The work to be performed in the Sprint is planned at the Sprint Planning. This plan is created by the collaborative work of the entire Scrum Team. Sprint Planning is time-boxed to a maximum of eight hours for a one-month Sprint. For shorter Sprints, the event is usually shorter. The Scrum Master ensures that the event takes place and that attendants understand its purpose.
The Scrum Master teaches the Scrum Team to keep it within the time-box. Sprint Planning answers the following:
- What can be delivered in the Increment resulting from the upcoming Sprint?
- How will the work needed to deliver the Increment be achieved?
The Development Team works to forecast the functionality that will be developed during the Sprint. The Product Owner discusses the objective that the Sprint should achieve and the Product Backlog items that, if completed in the Sprint, would achieve the Sprint Goal. The entire Scrum Team collaborates on understanding the work of the Sprint.
By the end of the Sprint Planning, the Development Team should be able to explain to the Product Owner and Scrum Master how it intends to work as a self-organizing team to accomplish the Sprint Goal and create the anticipated Increment.
The Daily Scrum is a 15-minute time-boxed event for the Development Team to synchronize activities and create a plan for the next 24 hours. This is done by inspecting the work since the last Daily Scrum and forecasting the work that could be done before the next one. The Daily Scrum is held at the same time and place each day to reduce complexity.
The Development Team uses the Daily Scrum to inspect progress toward the Sprint Goal and to inspect how progress is trending toward completing the work in the Sprint Backlog. The Daily Scrum optimizes the probability that the Development Team will meet the Sprint Goal. Every day, the Development Team should understand how it intends to work together as a self-organizing team to accomplish the Sprint Goal and create the anticipated Increment by the end of the Sprint. The Development Team or team members often meet immediately after the Daily Scrum for detailed discussions, or to adapt, or replan, the rest of the Sprint’s work.
The Scrum Master ensures that the Development Team has the meeting, but the Development Team is responsible for conducting the Daily Scrum.
Daily Scrums improve communications, eliminate other meetings, identify impediments to development for removal, highlight and promote quick decision-making, and improve the Development Team’s level of knowledge. This is a key inspect and adapt meeting.
Development Teams deliver an Increment of product functionality at least every Sprint, but not limited to only once per Sprint. The Development Team may deliver an Increment more than once a Sprint.
A Sprint Review is held at the end of the Sprint to inspect the Increments and adapt the Product Backlog if needed. During the Sprint Review, the Scrum Team and stakeholders collaborate about what was done in the Sprint. Based on that, and any changes to the Product Backlog during the Sprint, attendees collaborate on the next things that could be done to optimize value.
The result of the Sprint Review is a revised Product Backlog that defines the probable Product Backlog items for the next Sprint. The Product Backlog may also be adjusted overall to meet new opportunities.
The Sprint Retrospective is an opportunity for the Scrum Team to inspect itself and create a plan for improvements to be enacted during the next Sprint. The Sprint Retrospective occurs after the Sprint Review and prior to the next Sprint Planning. The Scrum Master ensures that the event takes place and that attendants understand its purpose.
The purpose of the Sprint Retrospective is to:
- Inspect how the last Sprint went with regards to people, relationships, process, and tools
- Identify and order the major items that went well and potential improvements
- Create a plan for implementing improvements to the way the Scrum Team does its work
By the end of the Sprint Retrospective, the Scrum Team should have identified improvements that it will implement in the next Sprint.
4. SCRUM ARTIFACTS
The Product Backlog is an ordered list of everything that might be needed in the product and is the single source of requirements for any changes to be made to the product. The Product Owner is responsible for the Product Backlog, including its content, availability, and ordering.
A Product Backlog is never complete. The earliest development of it only lays out the initially known and best-understood requirements. The Product Backlog evolves as the product and the environment in which it will be used evolves. The Product Backlog is dynamic; it constantly changes to identify what the product needs to be appropriate, competitive, and useful. As long as a product exists, its Product Backlog also exists.
The Product Backlog lists all features, functions, requirements, enhancements, and fixes that constitute the changes to be made to the product in future releases. Product Backlog items have the attributes of a description, order, estimate and value. Higher ordered Product Backlog items are usually clearer and more detailed than lower ordered ones. More precise estimates are made based on the greater clarity and increased detail; the lower the order, the less detail.
As a product is used and gains value, and the marketplace provides feedback, the Product Backlog becomes a larger and more exhaustive list. Requirements never stop changing, so a Product Backlog is a living artifact. Changes in business requirements, market conditions, or technology may cause changes in the Product Backlog.
The Sprint Backlog is the set of Product Backlog items selected for the Sprint, in support of the Sprint Goal. The Sprint Backlog is a forecast by the Development Team about what functionality will be in the next Increment and the work needed to deliver that functionality into a “Done” Increment.
The Sprint Backlog makes visible all of the work that the Development Team identifies as necessary to meet the Sprint Goal.
The Sprint Backlog is a plan with enough detail that changes in progress can be understood in the Daily Scrum. The Development Team modifies the Sprint Backlog throughout the Sprint, and the Sprint Backlog emerges during the Sprint. This emergence occurs as the Development Team works through the plan and learns more about the work needed to achieve the Sprint Goal.
As new work is required, the Development Team adds it to the Sprint Backlog. As work is performed or completed, the estimated remaining work is updated. When elements of the plan are deemed unnecessary, they are removed. Only the Development Team can change its Sprint Backlog during a Sprint. The Sprint Backlog is a highly visible, real-time picture of the work that the Development Team plans to accomplish during the Sprint, and it belongs solely to the Development Team.
The Increment is the sum of all the Product Backlog items completed during a Sprint and the value of the Increments of all previous Sprints. By the end of a Sprint, the new Increment must be “Done,” which means it must be in useable condition and meet the Scrum Team’s definition of “Done.” It must be in useable condition regardless of whether the Product Owner decides to actually release it.
When a Product Backlog item or an Increment is described as “Done,” everyone must understand what “Done” means. Although this varies significantly per Scrum Team, members must have a shared understanding of what it means for work to be complete, to ensure transparency. This is the definition of “Done” for the Scrum Team and is used to assess when work is complete on the product Increment. The purpose of each Sprint is to deliver Increments of potentially releasable functionality that adhere to the Scrum Team’s current definition of “Done.”